Scaling of the conductivity in icosahedral Al-Pd-Re metallic samples

Temperature dependence of electrical conductivity {σ} is investigated for a set of icosahedral (i-)Al70.5Pd₂₁Re8.5 samples. We focus on ribbon samples with resistance ratios R=ρ(4 K)/ρ(300 K) below 20. We show these samples are on the metallic side of a metal-insulator transition. We analyze our σ(T) data between 400 mK and 300 K with the one-parameter scaling theory of the Mott-Anderson metal-insulator transition. To the best of our knowledge, this is the first overall approach covering all the metallic samples of this system and a large temperature range up to 300 K. This interpretation highlights the relevance of the critical regime close to the metal-insulator transition, regime that is characterized by an inelastic scattering length smaller than the metallic correlation length {ξ}. Consequences for insulating i-Al-Pd-Re samples are also discussed.